Indicator



z Nov. 26, 1929. E. s. PEARCE ET AL 7,

wmcnon Filed May 12. 1926. 2 Sheets-Sheet 1 I wmv rolas A TTORNEYJ Nov.26, 1929.

E. s. PEARCE ET AL.

Filed May 12. 1926 INDICATOR 2 Sheets-Shag; 2

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I ATTORNEYS Patented Nov. 26, 1929 more states rinses ears-Ear GFFECEEDWIN s. PEARCE AND EDMOND c. Katrine, or INDIANAPOLIS, INDIANAINDICATOR Application filed May 12,

Tiis invention relates to indicators, and more particularly to anindicator or gauge for use on locomotives, operable by the exhaust backpressure toindicate to the locomotive g; engineer at all times whetherhis reverse lever is at the proper point oi cut-off for maximumeliicienoy of operation under the particular operating conditions thenobtaining, and, further, if the reverse lever is not Set is for theproper cut-off, will indicate directly in which direction the engineershould move the lever to obtain maximum efiiciency. The device may,therefore, be termed a directreading indicator for adjusting cut-oil.

It should be understood that the exhaust back-pressure in any locomotiveat any time is determined by four conditions, namely: speed, boilerpressure,throttle opening, and cut-oft, and that for any givenlocomotive there is a particular back-pressure at which it will operateat maximum eii'iciency. It,

then, the locomotive be operated constantly at that back-pressure, themaximum economy and capacity possible at any and every point throughoutits operating range will be obtained. ()rdinarily the engineman hooksdown the reverse lever at low speeds and on heavy pulls and hooks it upas speed increases, making the shifts in its position as his judgmentdictates, and basing his judgment principally upon the sound of theexhaust. While this is done, of course, to utilize the steam expansivelyas speed increases and to reduce back-pressure, it is only anapproximation of the conditions of economy which would ob tain were thelocomotiveto be operated with certainty at a predetermined constantbackpressure, Any change in speed, boiler pres-. sure, or throttleopening, or two or all of them, obviously will cause a change in thebackpressure, which, if the cut-0E be suitably altered, may becompensated for, that is, the back-pressure may be maintainedsubstatially constant by proper manipulation of the reverse lever fromtime totime.

The primary object of the present invention is, therefore, the provisionof an im proved gauge, actuatedby the locomotive back-pressure, to give,at all times, a positive indication to the engineman whether the reofthe moving parts of the apparatus, and

1926. Serial No. 108,474.

verse lever is in the position to maintain a certain predeterminedexhaust back-pressure under the particular operating conditions existentat the moment, and, if it is not in that position, to indicate directlywhether the reverse lever should be hooked up or hooked down, that is,whether the cut-off should be shor ened or lengthened in order torestore the back-pressureto the predetermined point.

This invention is an improvement upon that disclosed in our co-pendingapplication, Serial No. 63,827, filed October 21, 1925, and, in additionto the attainment of objects and advantages similar to those enumeratedin said application, the present invention provides a mechanism ofgreater simplicity, fewer parts, more positive action, greater freedomfrom friction, decreased cost of manufacture, installation andmaintenance, and easier and more accurate adjustment.

How all these advantages, and otners which Will doubtless occur to thoseskilled in'the art, are attained, will appear from the followingdescription of the preferred embodiment of theinvention, reference beinghad to the accompanying drawings, wherein- Fig. l is'a front elevationof the apparatus; and; V

Fig.2 is a sectional view of the same taken on the line 22 of Fig. l

In general, the device com-prises a pressure chamber A havinganenclosing cap or cas-' ing member 2, a chamber B thereabove having acasing memberS within which are most the indicator proper C having a capor casing, l with a glassfront 5. The casings 2 and 3 are securedtogether, as by the screws 6, and the casing 4 is secured to the casing3 by suitable screws 7 passing through the dial 8 at each side thereof.The assembled device thus makes one compact unit, with a tight lionsing, capable of ready application to the backhead of the boiler, or ofany other convenient mounting in the cab of the locomotive where itsindi'c'ation may' be observed by the engineman. 7

- The pressure chamber A, having a suitable pipe connection 9, containswithin it an elongating or bellows diaphragm 10 mounted on a peripheralring 11 pinched between the cap 2 and the lower part of. easing 3.Through the disc 12 of the diaphragm passes a spindle or bolt 13extending up through a of the diaphragm by contact with the abutment orannular boss 18 on the bottom of casing 3. The downward movement of thediaphragm is limited by contact of the head 19 of the spindle 13 with abolt or screw plug 20 screwed into the bottom of the cap. 2 against anadjusting washer 48. On the upper end of the bolt 13 is screwed orotherwise mounteda cap piece 21 having ahardened point 22, the cap piecemaintaining firmly in place the shoulder 15 and spacer 16, and thehardened point being adapted to bear within a concavity or depression onthe under side of a rocking member or lever 23 in chamber B.

Within ,the operating chamber B is the lever 23 having one end fulcrumedon pin 24 and the other or free end engaging a push rod 25, the latterhaving a pointed end 26 adapted to rest in a cup or depression in thelever. Intermediate the ends of the lever are two concavities onopposite sides thereof,

the lower adapted to receive the point 22 already referred to, and theupper adapted to receive the pointed end 27 of a rod 28 which carries afixed collar 29 against which a spring 30 is adapted to bear, the upperend of the spring seating on the bottom of .i

tension adjuster 31 which is screwed into the top of the casing 3. Theadjusting plug and its lock-nut 32 may have holes 33'and 34,respectively, for the insertion of any convenient tool for turning them.The spring 30 we have shown as being made of two lengths 30 and 30 ofcommercially available size, with a seating collar'or guide ring 30between them. By the use of a long spring we obtain a greater travel,and, consequently, greater movement of the lever 23' for" any givenchange in back pressure, which is desirable V for the increased movementof the indicating hand thereby effected. The ring 30 with its 1Aretaining jnut'41' may be screwed on the outer end ofithe shaft, and ascrew 42 is pro- :vided forthe setting orfadjustment of the pointer onthe shaft. A light tension spring 43, connected at one end to the lever38, and

at the other end to a fixed point, as, for

example, to the guide 36, takes up any lost motion in the indicatorparts, and exerts just suflicient pull. to insure the pointers move menttoward the left when the lever 23 is moving downward during a decreasein backpressure. The dial 8, as clearly shown in Fig. 1, has a mark 44midway of the sides, with the legend Hold therebelow. To one side of thehold position is a suitable inclication to hook down the reverse lever,and to the other side is an indication to hook up.

For the moving parts of the apparatus, we have provided lubricationmeans consisting of oil cups 4,5, 46, and 47, adapted to lubricaterespectively the indicator shaft 39, the sliding contact between rod 28and tension adjuster 31, and the pivot pin 24. V

The initial adjustment and the operation of the device are substantiallyas follows:

The plug 20, at the bottom of the pressure chamber, is unscrewed and theadjusting washer 48 removed, after which the plug is replaced and runfull in, bearing against the head 19 of spindle 13. 1Vith the plugscrewed all the way in, the diaphragm 10 is held at the center of itstravel. By means of the adjusting screw 42, the indicating hand 40 isthen set on its shaft 39 so that it points to the Hold mark 44'on thedial. The tension on the spring 30 is next adjusted, and, for purposesof illustration, let us assume that the locomotive to which the deviceis applied must be operated, for greatest efficiency, at a constantback-pressure of 10 pounds. Fluid pressure through a test gauge isadmitted by pipe 9 to chamber A, and bymeans of the adjusting plug 31and lock nut 32, the compression of spring 30 is adjusted, so that thepointer 40 will be opposite the mark Hold when the pressure, as shown onthe test gauge, is 10 pounds. In other words, for any particularlocomotive, the adjustment of the spring 30 must be such as to balancethe pointer at mid-position against a pressure equalto .thatback-pressure at which it is desired to operate that particularlocomotive.

During operation of the engine, pressure from the exhaust cavities ofthe cylinders, or from any suitable point in the exhaust line (notshown) is admitted through the connection 9 to the chamber A, tending tocompress the diaphragm, which, in the absence of such pressure,has'expanded under the force exerted by spring 30 until the head 19 isin contact with plug 20, the pointer 40 being at that time over theposition Hook down at the left of as speed increases, the back-pressureincreases and compresses the diaphragm againstthe force of spring 30,rocking the lever 23 upward, and actuating rod 25, lever 38 and shaftthe dial. As the throttle is opened, and/or 39 to move the pointer 40toward Hold position on the dial. After the point Hold has been reached,a further increase in throttle opening or speed, or an increase inboiler pressi e, or further increase in any two or more of them, willcause the pointer to move still farther to the right, over the regionvIndicator 1 lhandover Reason for indication Awon Cf engmeman and resultregion Down Drop in back-pressure below Moves reverse lever pressure atHold due to down, lengthening decrease in speed, boiler prescutofi andrestoring sure or throttle opening, or back-pressure. H combination oftwo or all of a n d move 5 to them. Hold position.

Up Rise in back pressure above Moves reverse lever pressure at Hold, dueto up, shortening eutincrease in speed, boiler presoil an (1 re ducin gsure, or throttle opening, or back-pressure. Hand combination of any twoor moves to Hold" all of them. position.

Hold No change in speed, boiler pres- Does not move reverse sure, orthrottle opening. lever.

It Will be obvious that our device is capable of ready adjustment forany particular installation, since the spring tension adjusting plug 31is accessible without the opening or removal of any part of theapparatus. The lubrication means is equally accessible, and very simpleand reliable in operation. The moving parts offer a minimum of friction,resulting, of course, in positive and accurate action, and the wholestructure, while rugged enough to withstand any shocks imposed by theexhaust steam pressure, provides, by means of the long spring and theelongati J or bellows diaphragm in combination with themovement-multiplying levers, a suficiently long travel of the indicatinghand to register even a slight change in pressure, one

sound difference in ressure for instance be- 4. 7

ing snihcient to cause a movement oi the pointer nearly half-way acrossthe dial.

Vie claim l. A. direct-reading indicator for adjusting locomotivecut-off comprising, in combination, a movable member, abellows-diaphragm actuated by locomotive eXh aust pressure adapted toexert a force on one side of said member, tension means adapted to exertforce on the other side of said member to position it variably inproportion to variat-ions in the exhaust pressure, and indicating meansactuated by said member.

2. A. direct-reading indicator for adjusting locomotive cutoii'comprising, in combi- 11 tion, a rocking member, phragm actuated bylocomotive exhaust pressure adapted to exert a force on one side of salemember,tension means adapted to exert a "force on the other side of saidmember to position it variably in proportion to variations in theexhaust pressure, and indicating means actuated by said member.

A direct-reading indicator for adjusting locomotive cut-oil comprising,in combination, a rocking member, means actuated by locomotive exhaustpressure adapted to exert a i orce on one side of said member, tensionmeans adapted to exert a force on the other side of said member toposition it variably in proportion to variations in the exhaust.pressure, and indicating means actuated by saidmembor, with anindicating dial associated therewith, together with means for adjustingthe pressure of the tension means.

A direct-reading indicator for adjusting irlCOIilOilVG cut-oficomprising, in combination, a flexible bellows diaphragm, means foradmitting locomotive back-pressure thereto, tension means, a leveractuated in one direction by the bellows diaphragm and in anotherdirection by the tension means and adapted to multiply the movementimparted to it, said lever being balanced by the tension means in.various positions in accordance with variations in the back-pressure,and indicating means actuated by said'lever.

5. ii, direct-reading indicator. for adjusting locomotive cut-oncomprising, in combination, a bellows diaphragm member, means for admitk locomotive back-pressure thereto, tension means, a lever actuated inone ction by said member and in another direc on by the tension meansand adapted to ply the movement imparted to it, and i.ating meansactuated by said lever, including a movable indicating member and astationary member in association therewith.

6. A direct-reading indicator for adjusting locomotive cutolicomprising, in combination, a bellows diaphragm member, means foradmitting locomotive back-pressure thereto, tension means, a leveractuated in one direction by said member and in another direction bythetension means and adapted to a bellows diamultiply the movementimparted to it, and

in each direction, and means for adjusting the relative positions ofsaid member and said indicating hand comprising means adapted to holdthe member atthe center of its travel against the pressure of thetension device, and means for shifting the position of the 7 hand Withrelation to the said operative connections. v

8. In a back-pressure-operated indicator for adjusting locomotivecut-off, the combination of movable mechanism acted upon and variable inposition overvits range of travel by changes in locomotivebaclepressure, indicating mechanism actuated by said movable mechanism,a fixed element associated with said indicating mechanism to give anormal cut-off indication when said mechanism is at a point intermediateits limits of movement and having means on each side thereof indicatingvariations from said normal point, and means of adjusting saidindicating mechanism relativeto said movable mechanism and said fixedelement so that it may be set at said intermediate normal point whensaid movable mechanism is positioned at any given point of its travelunder the influence of said baclcpressure. a

9. In a back-pressure-operated indicator for adjusting locomotivecut-off, the combination of movable mechanism acted upon and variable inposition over its range of travel by changes in locomotiveback-pressure, indicating mechanism actuated by said movable mechanism,a fixed element associated With said indicating mechanism to give anormal cut-off indication When said mechanism is at a point intermediateits limits of movement and having means on each side thereof indicatingvariations from said normal point, and means of adjusting saidindicating mechanism relative to said movablemechanism and said fixedelement so that it may be set at said intermediate normal point whensaid movable mechanism vis positioned at any given point of its travelunder the influence of said back-pressure, said movable mechanismincluding an elongated bellows diaphragm and a co-operating spring ofacorrespondingly long range of movement and of a relatively smalldifference of resistive power for a given movement. 7

' 10. In a back-pressure-operated indicator,

the combination of mechanism actuated 'in one direction by locomotiveback-pressure, yieldingly resistive means ad ustable for pressureandacting onsaid mechanism in a direction opposite to the force exerted bysaid back-pressure, indicating mechanism act-uated by saidfirst-mentioned mechanism and adjustable relative thereto so that it maybe set for a predetermined indication When said f mechanism has beenmoved to the center of its travel by theback-pressure and under any agiven adjustment of the yieldingly resistive 11 In abacl(-pressure-operated indicator, the combination of mechanism actuatedin one direction by locomotive back-pressure,

.yieldingly resistive means adjustable for pressure and acting on saidmechanism in a direction opposite to the force exerted by saidback-pressure, indicating mechanism actuated by said first-mentionedmechanism and adjust-able relative thereto so that it may be set for apredetermined indication when said mechanism has been moved to thecenter of its travel by the back-pressure and under any given adjustmentof the yieldingly resistive means, together with a housing and means formaking the adjustment of the mechanism from the outside of the housing.

v12. In mechanism of the character described, the combination of ahousing, a lever pivotally mounted therein, means actuated byback-pressure and adapted to bear against said lever, tension meansadapted to bear against the lever in an opposite direction, indicatingmechanism actuated by said lever with a dial co-operating therewith, anda pressure-adjusting device for the tension means operable from withoutthe said housmg.

13. An indicator of the character described comprising, in combination,a casing, a flexible diaphragm therein, forming, with a, portion of saidcasing, a pressure chamber,

means for admitting fluid pressure to said chamber, a tension device insaid casing, a pivoted member in the casing positioned by and betweenthe diaphragm and the tension device, indicating mechanism operable bysaid pivoted member, an adjustable stop operable from outside the casingto position said diaphragm during adjustment of the indicatingmechanism, and an adjusting means for the tension device operable fromoutside the casing. V

14.'In mechanism of the character described, a flexible member adaptedto be actuated in one direction by fluid pressure, ad

justable tension means adapted to actuate it

